Construction workers and painters are oftentimes required to work at some elevation above their normal reach. Conventionally such workers have used ladders and scaffolds to extend their reach. The most common scaffolding is erected on the ground and utilizes a plurality of vertical, horizontal, and bracing elements to support a platform upon which the worker stands. When the area thus brought within the workers' reach is completed the scaffolding must be added to vertically or, more troublesomely, the entire scaffolding must be moved laterally. In either instance the workers must descend from the scaffolding to enable the placement of the platform to a new work area. Another common type of scaffolding is suspended from the top of a structure by ropes and pulleys, e.g. window washing and sign painting equipment, and provides the worker with freedom of movement in the vertical direction, but is not readily mobile in the horizontal direction.
A particular type of construction which has traditionally used scaffolding is the installation of roof panels on purlins such as are found at gas stations or other open air shelters. In this instance the workers require a stable work platform inasmuch as there is no adjacent wall to utilize for support and the workers are normally using both hands to install the roof panels overhead. Conventional suspended scaffolding as hereinabove described is not stable enough and is not readily mounted to this type structure, nor does it provide the lateral movement necessary. Ground scaffolding is cumbersome and inconvenient for this type work since it must be moved often in the course of installing a complete roof.